Dose effects of spondo mutation (IMAGE) Duke University Caption A normal zebrafish spine is shown at top, in the middle a fish which has one copy of the mutated spinal development gene, and bottom, a fish with two copies of the mutant gene. Note the split vertebrae toward the right of the middle specimen. Credit Michel Bagnat Lab, Duke University Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.